Method of cleaning elongated metal shapes



Oct. 3, 1939. J. M. HILBISH ET AL METHOD OF CLEANING ELONGATED METALSHAPES 2 Sheets-Sheet l Filed Oct. 5, 1938 ATTORNEY.

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IIIII Oct. 3, 1939. J. M. HILBISH ET AL 2,174,330

METHOD OF CLEANING ELONGATED METAL SHAPES Filed Oct. 5, 1938 2Sheets-Sheet 2 INVE NTORS Z ATTORNEY.

Patented Oct. 3, 1939 UNITED STATES PATENT OFFICE HAPES Joseph M.Hilbish and John K. McCahan, Pittsburgh, Pa.

Application October 5,

1 Claim.

This patent application is in part a division of our joint patentapplication Serial Number 133,991, filed in the United States PatentOffice on March 31, 1937 which matured into Patent No.

62,134,557, October 25, 1938 and also in part a division of our jointpatent application Serial Number 205,936, filed in the United StatesPatent Office on May 4, 1938.

Our present invention relates to improved methods for cleaning scale,rust, pitting and the like from the surfaces of elongated metal objectssuch as steel billets, slabs, bars, rods and other shapes, and also forcoating the clean shapes with substances to prevent further corrosion.

Billets, slabs and other shapes of unfinished steel are characterized byrolled-in scale, rust and other surface impurities and defects whichmust be removed before the shapes are further fabricated or brought intofinished form.

The method usually employed for this purpose is the pickling of theshapes in an acid bath.

This method is time-consuming and expensive,

and the length of the shapes which may be pickled is of course limitedby the capacity of the pickling vat. Moreover, the acid of the bath islikely to pit the metal and especially in the case of special steels theconsequent loss is substantial.

The average cost of the pickling treatment is from one to fifteendollars per ton of steel, while the commercial use of our invention hasreduced this cost to as low as from twenty-five cents to fifty cents perton.

Another method in frequent use for cleaning rusted and pitted steelbars, rods, tubes and other elongated shapes is to use hand or machinebrushing, one article at a time being treated.

The records of one of the large steel mills disclose that it takes at anaverage approximately forty minutes to clean by brushing a sixteen footlength of No. 12 gauge band steel of 2% inches in width, while with theuse of our invention three tons of like material are effectively cleanedin twenty minutes.

Sand blasting is another method of cleaning in use, but with this methodelongated shapes must be separately treated and, owing to the time andlabor consumed, the expense is very much greater than in the use of ourmethod.

In our method we load a quantity of the elongated shapes into acylindrical container of greater interior length than the lengths of theshapes and of greater cross-sectional capacity than the combinedcross-sectional area of the shapes. We then rotate the container on itslon- 55 gitudinal axis and simultaneously tilt the con- 1938, Serial No.233,404 (01. 51-278) tainer on its longitudinal axis alternately inopposite directions. 3

The rotation of the cylindrical container causes the individual shapesto climb or be drawn upwardly along the interior wall of the containerin the direction of rotation, which action is increased by providing thecontainer with a polygonal side wall instead of one of truly annularform. As the shapes are raised they fall back on the remainder of theshapes, resulting in a continuous series-of hard impacts which loosenthe scale, rust and other substances, and the tilting of the containeralternately in opposite directions causes an attrition between thelateral surfaces of the shapes temporarily in motion and thosetemporarily at rest or moving at a different speed. This results inattrition which further loosens the scale and rust and dislodges thesame so that it accumulates in the lower portion of the container. Thecombined use of impact and attrition in our method also effects thesuccessful removal of pitting.

The cleaning operation may be expedited by placing in the container aquantity of sand, coke dust, hard metal scale or other suitable abrasivematerial.

Again, after metal shapes have been cleaned of rust, scale and othersurface defects, the cleaned surfaces are more susceptible to rustingthan they were before cleansing.

In the practice now in general use, the cleaned shapes are coated;either by brushing or dipping, with some corrosion-preventing substance,usually a compound containing tallow or graphite or both. Thisoperation, accomplished either by brushing or dipping, is time consumingand expensive, especially in the case of elongated shapes.

In our method we place the cleaned elongated shapes in the containertogether with a sufficient quantity of the corrosion-preventingcompoundand then rotate and tilt the container, inthe manner above described,and in a very short time, a fraction of the time required when themethods of coating above referred to are employed, an evenly distributedand adequate coating of the substance is applied'to the surfaces of theshapes.

The rotation and tilting of the container during the cleaning operationmay be such as to impart an orbital movement to the opposite ends of thecontainer, but where the shapes to be cleaned are of relatively smallcross-section, such for instance as relatively slender bars, rods andthin strips, such an orbital movement tends to twist and bend the shapeslongitudinally and sometimes even entangling them with each other, sothat the same require subsequent straightening.

Therefore as a further improvement in our invention we rotate thecylinder on its longitudinal axis and simultaneously tilt itlongitudinally alternately in opposite directions but confine suchtilting to substantially the same vertical plane. By this means anytendency of the shapes tobecome bent or twisted is avoided and thecleaned shapes do not require subsequent straightening or othercorrection.

In the accompanying drawings, wherein we have illustrated apparatussuitable for working our invention,

Fig. 1 is a side elevation of one form of suitable apparatus.

Fig. 2 is a cross-sectional view taken along the line II-II in Fig. 1.

Fig. 3 is a like view taken along the line III-III in Fig. 1.

Fig. 4 is a like View taken along the line IV-IV in Fig. 1.

Fig. 5 is a broken elevation of one of the removable end closures.

Fig. 6 is a side elevation of another form. of suitable apparatus.

Fig. 7 is a cross-sectional View taken along the line V'.[IVII in Fig.6.

Fig. 8 is a cross-sectional view taken along the line VIIIVIII in Fig. 6showing the hoisting mechanism.

Referring first to Figs. 1 to 6 inclusive, of the drawings, l representsa longitudinally extended cylindraceous container of sufiicient lengthtoreceive metal shapes of the proper lengths. In practice we find thatin many instances the container should be long enough to receive bars,rods and other shapes of at least seventy-five feet in length. As willlater appear, the interior length of the container should be greaterthan that of the material which is to be cleaned or coated.

The cross-sectional shape of the container l is preferably polygonal,such as octagonal, instead of annular, since where the container is atrue cylinder, the bars, rods or other shapes when the container isrotated, tend to slide down and remain more or less quiescent in thebottom of the container. while where the container is of polygonal crosssection the rotation of the container tends to carry the articles upalong the side of the container whence they fall down and thus thearticles are continuously impacting against each other.

Thus any portion of the bar or other shape moves in an orbital pathtransverse to the axis of the container.

Adjacent either end of the container the latter is supported in asuitable manner.

Thus we provide a pair of stands 2 mounted on either end of a base 3.

The stands each may be formed of a pair of parallel plates 4 which arein spaced relation to each other and preferably have arcuate upperperimetral edges as shown in Figs. 2 and 3.

The plates 4 are provided with registering.

circular openings 5.

Between the plates 4 of each stand 2 is moun ed a circular head6,concentric with the opening, which is rotatably supported in place by aplurality of grooved rollers 1 mounted between the plates 4 as on axlessupported at their ends by said plates.

Each of the heads 6 is provided with an opening 8 of the proper size andcontour to snugly receive the container l and the heads are fixed to thecontainer in any suitable manner, as by welding.

The openings 8 are not concentric with the heads 6 but eccentricthereto, as illustrated in the drawings, the head adjacent one end ofthe therefore their surfaces rub against each other,

resulting in attrition.

Intermediate of the ends of the container the perimetral surface of thesame is provided with one or more radially extending annular flanges 9to the side surface of which is bolted or otherwise secured a ringsprocket it connected by a drive chain It with a power-driven sprocketl2.

The ends of the container are provided with removable closures to permitthe loading and unloading of the container.

Thus we show the extremities of the container provided with outwardlyextending annular flanges l 3 provided with bolt holes. M represents thecircular end closures or lids of like diameter as the flanges l3 andprovided with key-hole bolt openings Hi, the diameter of the openingsbeing large enough to give clearance to the heads of the bolts I505 andthe smaller slotted portions of the openings being of the width to giveclearance to the shank of the bolts. The openings [5 are so disposedthat the head it may be turned into position with the larger portions ofthe openings i5 registering with the heads of the bolts when the lid maybe placed in position with bolts protruding through the openings. Thelid is then rotated sufiiciently to move the bolts into the slottedportions of the openings and the nuts are then tightened on the boltsand the lids clamped in place. To remove a lid the nuts are loosened andthe lid rotated to bring the bolts into registration with the largerportions of the openings.

To assist and expedite the cleaning action we may and usually do placesome suitable cleaning material in the container, such as sand, cokedust corrosion resisting properties, such material is k placed with themetal objects in the container, the end-closures are put in place, andthe container is rotated. As the result of the rotary and tiltingmovements of the container a uniformly distributed coating of eventhickness is quickly applied to the objects.

We have found that a suitable compound for this purpose may be producedby mixing tallow, kerosene, graphite and sawdust or some other suitablecarrier. Thus we have successfully employed the proportions of tenpounds of tallow, one gallon of kerosene and two and one-half pounds ofgraphite.

Where the shapes are slender or of relative small cross-sectional area,we find that where the container is given what may be termed an orbitalmovement as above described in connection with Figs. 1 to 5, inclusive,there is a tendency for the shapes to become bent, twisted and in somecases intertwined with each other, thus requiring straightening or otherreworking before use or additional fabrication.

In Figs. 6 to 8, inclusive, of the drawings, we illustrate a form ofapparatus wherein such shapes may be cleaned and also coated withoutdanger of such distortion or intertwining and wherein the alternatetilting of the container in opposite directions is confined tosubstantially one vertical plane, thus obviating orbital movement of thecontainer.

This apparatus is as follows, reference being had to Figs. 6 to 8inclusive of the drawings.

I6 represents a cradle comprising two sets of transversely disposedsquare plates I! held in spaced relation by the diagonal load membersI3, and mounted on the base platform I9. 20 represents a top platformsupported by the plates I1.

Each set of plates I1 is held in spaced relation to receive between thesame the grooved idle rollers 2I which rotate on axle pins 22 held insaid plates. The axes of the pins 22 are positioned to intersectdiagonal lines drawn from the corners of the plates I! and areoppositely disposed to one another in quadrangular relation so as tointersect the circumference of an imaginary circle drawn from theintersection of said diagonal lines as a center.

A circular opening 23 having the same center is cut in each plate,thereby exposing a portion of the perimetral surface of the rollers 2!as shown in Fig. '7.

24 represents a pair of circular disks interposed between sets of platesI1 and the perimetral edge of which engages the grooves of the rollers2I. Thus a disk 24 is rotatably mounted upon the rollers 2! of each setof plates Il.

These disks 24 are each provided with a concentric opening 25 to receivethe container I which is fixed to the disks as by welding. The ends ofsaid container is provided with removable end closures as described inconnection with the previous figures of the drawings.

26 represents a motor mounted on the platform 20 and coupled to thespeed reducer 21 to drive the shaft 28. 29 represents a sprocket pinionfixed on the shaft 28 and connected by the chain 30 with a ring sprocket3| surrounding and fixed to the container I. Thus the container I isrotated by the motor 25.

The base I9 of the cage I6 is pivotally supported intermediate of itsends on the aligned horizontal bearings 32 mounted on suitablefoundations 33. Thus the container may be tilted in a vertical plane onits longitudinal axis. The axis of tilting is adjacent one end of thecontainer.

The other end of the drum I is supported by a hanger 34 comprising ayoke 35 which is provided with an eye 35 at its upper end to receive thehook 31 of a hoist or lift 38. The lower or bifurcated ends of the yoke35 are provided with aligned bearings 39 arranged to receive the gudgeonends of the shaft 49. The intermediate portion of this shaft ispreferably square to permit the assembly of the parallel plates 4| onopposite sides thereof. These plates are similar to the plates I! inthat they are constructed to support the triangularly disposed pins 22which rotatably carry the three idler rollers 2!. The plates areprovided with aligned openings arranged to receive the container I andsupport the same by means of the circular disk track 24 riding on theidler rollers 2i. This structure permits the lift or hoist 34 to tiltthe container I about the axis of the bearings 32 while the container isbeing rotated.

Swiveled rollers 42 are provided on the ends of the the shaft 4!! and onthe upper end of the yoke 35. These rollers are arranged to ride on thewide vertically disposed tracks 43 and prevent the container from beingmoved laterally as the load is rolled and shifted therein. The hoist orlift 38 may be hydraulic, pneumatic or an ordinary electrically drivenhoist. In either case the valves 64 of the hydraulic or pneumatic hoistsmust be capable of being cracked so as to enable the operator to changethe speed of tilting the drum during the proper periods of its operatingcycle. The same character of control is required of the electricalhoist. The operator is thus enabled to control the rolling and shiftingof the load as the objects are being cleaned and coated. Thus a lifthaving a very quick or fast speed and a slow speed with a series ofintermediate steps therebetween is advantageous for use with thisapparatus. A short or quick lift or drop adjacent the upper or lowertilting positions of the container I creates a shock on the load thereincausing it to shift to the lower end thereof.

The method involved by the use of the structure illustrated in Figs. 6to 8, inclusive, has marked advantages compared to the structureillustrated by Figs. 1 to 5, inclusive, wherein the axis, upon which thecontainer is rotated, itself travels in an orbital path.

Where the container rotates on an axis which travels in an orbital path,rods and other shapes of considerable length and of relatively smalldiameter are likely to become bent, distorted and twisted about eachother, thus frequently ruining the material or necessitating astraightening operation. It has been found in the commercial use of thismodification that such deleterious results do not occur due to the factthat the axis of the container does not travel in an orbital path but ina vertical plane. This is a very important improvement of this inventionand efiects a very material saving both in labor and material.

We claim:

The method of conditioning the surfaces of elongated metal objects whichcomprises, placing a quantity of these objects in an enclosure, tiltingthe objects in a vertical plane to cause them to shift longitudinallyback and forth with their opposite ends alternately elevated above thehorizontal to produce attrition between the objects and the enclosureand between the objects themselves, and simultaneously rolling theobjects to promote their sliding action, thereby reducing the necessaryangle of tilting.

JOSEPH M. HILBISH. JOHN K. MCCAHAN.

